In the gastrocnemius muscle, besides the olfactory transduction mentioned above, the over-represented groups identified according to GO biological processes for obesity progression were those involved in the various cellular processes such as neuroactive ligand-receptor interaction, cytokine-cytokine receptor interaction, pathways associated with cancer, insulin signaling pathway, pathways associated with colorectal cancer, adipocytokine signaling pathway, type II diabetes mellitus, and cell adhesion molecules. The gene discussed is INS; the disease is obesity due to melanocortin 4 receptor deficiency.